src/httpfetch.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "socket.h" // for select()
  21 #include "porting.h" // for sleep_ms(), get_sysinfo()
  22 #include "httpfetch.h"
  23 #include <iostream>
  24 #include <sstream>
  25 #include <list>
  26 #include <map>
  27 #include <errno.h>
  28 #include "jthread/jevent.h"
  29 #include "config.h"
  30 #include "exceptions.h"
  31 #include "debug.h"
  32 #include "log.h"
  33 #include "util/container.h"
  34 #include "util/thread.h"
  35 #include "version.h"
  36 #include "main.h"
  37 #include "settings.h"
  38
  39 JMutex g_httpfetch_mutex;
  40 std::map<unsigned long, std::queue<HTTPFetchResult> > g_httpfetch_results;
  41
  42 HTTPFetchRequest::HTTPFetchRequest()
  43 {
  44         url = "";
  45         caller = HTTPFETCH_DISCARD;
  46         request_id = 0;
  47         timeout = g_settings->getS32("curl_timeout");
  48         connect_timeout = timeout;
  49         multipart = false;
  50
  51         useragent = std::string("Minetest/") + minetest_version_hash + " (" + porting::get_sysinfo() + ")";
  52 }
  53
  54
  55 static void httpfetch_deliver_result(const HTTPFetchResult &fetch_result)
  56 {
  57         unsigned long caller = fetch_result.caller;
  58         if (caller != HTTPFETCH_DISCARD) {
  59                 JMutexAutoLock lock(g_httpfetch_mutex);
  60                 g_httpfetch_results[caller].push(fetch_result);
  61         }
  62 }
  63
  64 static void httpfetch_request_clear(unsigned long caller);
  65
  66 unsigned long httpfetch_caller_alloc()
  67 {
  68         JMutexAutoLock lock(g_httpfetch_mutex);
  69
  70         // Check each caller ID except HTTPFETCH_DISCARD
  71         const unsigned long discard = HTTPFETCH_DISCARD;
  72         for (unsigned long caller = discard + 1; caller != discard; ++caller) {
  73                 std::map<unsigned long, std::queue<HTTPFetchResult> >::iterator
  74                         it = g_httpfetch_results.find(caller);
  75                 if (it == g_httpfetch_results.end()) {
  76                         verbosestream << "httpfetch_caller_alloc: allocating "
  77                                         << caller << std::endl;
  78                         // Access element to create it
  79                         g_httpfetch_results[caller];
  80                         return caller;
  81                 }
  82         }
  83
  84         FATAL_ERROR("httpfetch_caller_alloc: ran out of caller IDs");
  85         return discard;
  86 }
  87
  88 void httpfetch_caller_free(unsigned long caller)
  89 {
  90         verbosestream<<"httpfetch_caller_free: freeing "
  91                         <<caller<<std::endl;
  92
  93         httpfetch_request_clear(caller);
  94         if (caller != HTTPFETCH_DISCARD) {
  95                 JMutexAutoLock lock(g_httpfetch_mutex);
  96                 g_httpfetch_results.erase(caller);
  97         }
  98 }
  99
 100 bool httpfetch_async_get(unsigned long caller, HTTPFetchResult &fetch_result)
 101 {
 102         JMutexAutoLock lock(g_httpfetch_mutex);
 103
 104         // Check that caller exists
 105         std::map<unsigned long, std::queue<HTTPFetchResult> >::iterator
 106                 it = g_httpfetch_results.find(caller);
 107         if (it == g_httpfetch_results.end())
 108                 return false;
 109
 110         // Check that result queue is nonempty
 111         std::queue<HTTPFetchResult> &caller_results = it->second;
 112         if (caller_results.empty())
 113                 return false;
 114
 115         // Pop first result
 116         fetch_result = caller_results.front();
 117         caller_results.pop();
 118         return true;
 119 }
 120
 121 #if USE_CURL
 122 #include <curl/curl.h>
 123
 124 /*
 125         USE_CURL is on: use cURL based httpfetch implementation
 126 */
 127
 128 static size_t httpfetch_writefunction(
 129                 char *ptr, size_t size, size_t nmemb, void *userdata)
 130 {
 131         std::ostringstream *stream = (std::ostringstream*)userdata;
 132         size_t count = size * nmemb;
 133         stream->write(ptr, count);
 134         return count;
 135 }
 136
 137 static size_t httpfetch_discardfunction(
 138                 char *ptr, size_t size, size_t nmemb, void *userdata)
 139 {
 140         return size * nmemb;
 141 }
 142
 143 class CurlHandlePool
 144 {
 145         std::list<CURL*> handles;
 146
 147 public:
 148         CurlHandlePool() {}
 149         ~CurlHandlePool()
 150         {
 151                 for (std::list<CURL*>::iterator it = handles.begin();
 152                                 it != handles.end(); ++it) {
 153                         curl_easy_cleanup(*it);
 154                 }
 155         }
 156         CURL * alloc()
 157         {
 158                 CURL *curl;
 159                 if (handles.empty()) {
 160                         curl = curl_easy_init();
 161                         if (curl == NULL) {
 162                                 errorstream<<"curl_easy_init returned NULL"<<std::endl;
 163                         }
 164                 }
 165                 else {
 166                         curl = handles.front();
 167                         handles.pop_front();
 168                 }
 169                 return curl;
 170         }
 171         void free(CURL *handle)
 172         {
 173                 if (handle)
 174                         handles.push_back(handle);
 175         }
 176 };
 177
 178 class HTTPFetchOngoing
 179 {
 180 public:
 181         HTTPFetchOngoing(HTTPFetchRequest request, CurlHandlePool *pool);
 182         ~HTTPFetchOngoing();
 183
 184         CURLcode start(CURLM *multi);
 185         const HTTPFetchResult * complete(CURLcode res);
 186
 187         const HTTPFetchRequest &getRequest()    const { return request; };
 188         const CURL             *getEasyHandle() const { return curl; };
 189
 190 private:
 191         CurlHandlePool *pool;
 192         CURL *curl;
 193         CURLM *multi;
 194         HTTPFetchRequest request;
 195         HTTPFetchResult result;
 196         std::ostringstream oss;
 197         struct curl_slist *http_header;
 198         curl_httppost *post;
 199 };
 200
 201
 202 HTTPFetchOngoing::HTTPFetchOngoing(HTTPFetchRequest request_, CurlHandlePool *pool_):
 203         pool(pool_),
 204         curl(NULL),
 205         multi(NULL),
 206         request(request_),
 207         result(request_),
 208         oss(std::ios::binary),
 209         http_header(NULL),
 210         post(NULL)
 211 {
 212         curl = pool->alloc();
 213         if (curl == NULL) {
 214                 return;
 215         }
 216
 217         // Set static cURL options
 218         curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);
 219         curl_easy_setopt(curl, CURLOPT_FAILONERROR, 1);
 220         curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
 221         curl_easy_setopt(curl, CURLOPT_MAXREDIRS, 1);
 222
 223         std::string bind_address = g_settings->get("bind_address");
 224         if (!bind_address.empty()) {
 225                 curl_easy_setopt(curl, CURLOPT_INTERFACE, bind_address.c_str());
 226         }
 227
 228 #if LIBCURL_VERSION_NUM >= 0x071304
 229         // Restrict protocols so that curl vulnerabilities in
 230         // other protocols don't affect us.
 231         // These settings were introduced in curl 7.19.4.
 232         long protocols =
 233                 CURLPROTO_HTTP |
 234                 CURLPROTO_HTTPS |
 235                 CURLPROTO_FTP |
 236                 CURLPROTO_FTPS;
 237         curl_easy_setopt(curl, CURLOPT_PROTOCOLS, protocols);
 238         curl_easy_setopt(curl, CURLOPT_REDIR_PROTOCOLS, protocols);
 239 #endif
 240
 241         // Set cURL options based on HTTPFetchRequest
 242         curl_easy_setopt(curl, CURLOPT_URL,
 243                         request.url.c_str());
 244         curl_easy_setopt(curl, CURLOPT_TIMEOUT_MS,
 245                         request.timeout);
 246         curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT_MS,
 247                         request.connect_timeout);
 248
 249         if (request.useragent != "")
 250                 curl_easy_setopt(curl, CURLOPT_USERAGENT, request.useragent.c_str());
 251
 252         // Set up a write callback that writes to the
 253         // ostringstream ongoing->oss, unless the data
 254         // is to be discarded
 255         if (request.caller == HTTPFETCH_DISCARD) {
 256                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
 257                                 httpfetch_discardfunction);
 258                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, NULL);
 259         } else {
 260                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
 261                                 httpfetch_writefunction);
 262                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, &oss);
 263         }
 264
 265         // Set POST (or GET) data
 266         if (request.post_fields.empty()) {
 267                 curl_easy_setopt(curl, CURLOPT_HTTPGET, 1);
 268         } else if (request.multipart) {
 269                 curl_httppost *last = NULL;
 270                 for (std::map<std::string, std::string>::iterator it =
 271                                         request.post_fields.begin();
 272                                 it != request.post_fields.end(); ++it) {
 273                         curl_formadd(&post, &last,
 274                                         CURLFORM_NAMELENGTH, it->first.size(),
 275                                         CURLFORM_PTRNAME, it->first.c_str(),
 276                                         CURLFORM_CONTENTSLENGTH, it->second.size(),
 277                                         CURLFORM_PTRCONTENTS, it->second.c_str(),
 278                                         CURLFORM_END);
 279                 }
 280                 curl_easy_setopt(curl, CURLOPT_HTTPPOST, post);
 281                 // request.post_fields must now *never* be
 282                 // modified until CURLOPT_HTTPPOST is cleared
 283         } else if (request.post_data.empty()) {
 284                 curl_easy_setopt(curl, CURLOPT_POST, 1);
 285                 std::string str;
 286                 for (std::map<std::string, std::string>::iterator it =
 287                                         request.post_fields.begin();
 288                                 it != request.post_fields.end();
 289                                 ++it) {
 290                         if (str != "")
 291                                 str += "&";
 292                         str += urlencode(it->first);
 293                         str += "=";
 294                         str += urlencode(it->second);
 295                 }
 296                 curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE,
 297                                 str.size());
 298                 curl_easy_setopt(curl, CURLOPT_COPYPOSTFIELDS,
 299                                 str.c_str());
 300         } else {
 301                 curl_easy_setopt(curl, CURLOPT_POST, 1);
 302                 curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE,
 303                                 request.post_data.size());
 304                 curl_easy_setopt(curl, CURLOPT_POSTFIELDS,
 305                                 request.post_data.c_str());
 306                 // request.post_data must now *never* be
 307                 // modified until CURLOPT_POSTFIELDS is cleared
 308         }
 309         // Set additional HTTP headers
 310         for (std::vector<std::string>::iterator it = request.extra_headers.begin();
 311                         it != request.extra_headers.end(); ++it) {
 312                 http_header = curl_slist_append(http_header, it->c_str());
 313         }
 314         curl_easy_setopt(curl, CURLOPT_HTTPHEADER, http_header);
 315
 316         if (!g_settings->getBool("curl_verify_cert")) {
 317                 curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, false);
 318         }
 319 }
 320
 321 CURLcode HTTPFetchOngoing::start(CURLM *multi_)
 322 {
 323         if (!curl)
 324                 return CURLE_FAILED_INIT;
 325
 326         if (!multi_) {
 327                 // Easy interface (sync)
 328                 return curl_easy_perform(curl);
 329         }
 330
 331         // Multi interface (async)
 332         CURLMcode mres = curl_multi_add_handle(multi_, curl);
 333         if (mres != CURLM_OK) {
 334                 errorstream << "curl_multi_add_handle"
 335                         << " returned error code " << mres
 336                         << std::endl;
 337                 return CURLE_FAILED_INIT;
 338         }
 339         multi = multi_; // store for curl_multi_remove_handle
 340         return CURLE_OK;
 341 }
 342
 343 const HTTPFetchResult * HTTPFetchOngoing::complete(CURLcode res)
 344 {
 345         result.succeeded = (res == CURLE_OK);
 346         result.timeout = (res == CURLE_OPERATION_TIMEDOUT);
 347         result.data = oss.str();
 348
 349         // Get HTTP/FTP response code
 350         result.response_code = 0;
 351         if (curl && (curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE,
 352                                 &result.response_code) != CURLE_OK)) {
 353                 // We failed to get a return code, make sure it is still 0
 354                 result.response_code = 0;
 355         }
 356
 357         if (res != CURLE_OK) {
 358                 errorstream << request.url << " not found ("
 359                         << curl_easy_strerror(res) << ")"
 360                         << " (response code " << result.response_code << ")"
 361                         << std::endl;
 362         }
 363
 364         return &result;
 365 }
 366
 367 HTTPFetchOngoing::~HTTPFetchOngoing()
 368 {
 369         if (multi) {
 370                 CURLMcode mres = curl_multi_remove_handle(multi, curl);
 371                 if (mres != CURLM_OK) {
 372                         errorstream << "curl_multi_remove_handle"
 373                                 << " returned error code " << mres
 374                                 << std::endl;
 375                 }
 376         }
 377
 378         // Set safe options for the reusable cURL handle
 379         curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
 380                         httpfetch_discardfunction);
 381         curl_easy_setopt(curl, CURLOPT_WRITEDATA, NULL);
 382         curl_easy_setopt(curl, CURLOPT_POSTFIELDS, NULL);
 383         if (http_header) {
 384                 curl_easy_setopt(curl, CURLOPT_HTTPHEADER, NULL);
 385                 curl_slist_free_all(http_header);
 386         }
 387         if (post) {
 388                 curl_easy_setopt(curl, CURLOPT_HTTPPOST, NULL);
 389                 curl_formfree(post);
 390         }
 391
 392         // Store the cURL handle for reuse
 393         pool->free(curl);
 394 }
 395
 396
 397 class CurlFetchThread : public JThread
 398 {
 399 protected:
 400         enum RequestType {
 401                 RT_FETCH,
 402                 RT_CLEAR,
 403                 RT_WAKEUP,
 404         };
 405
 406         struct Request {
 407                 RequestType type;
 408                 HTTPFetchRequest fetch_request;
 409                 Event *event;
 410         };
 411
 412         CURLM *m_multi;
 413         MutexedQueue<Request> m_requests;
 414         size_t m_parallel_limit;
 415
 416         // Variables exclusively used within thread
 417         std::vector<HTTPFetchOngoing*> m_all_ongoing;
 418         std::list<HTTPFetchRequest> m_queued_fetches;
 419
 420 public:
 421         CurlFetchThread(int parallel_limit)
 422         {
 423                 if (parallel_limit >= 1)
 424                         m_parallel_limit = parallel_limit;
 425                 else
 426                         m_parallel_limit = 1;
 427         }
 428
 429         void requestFetch(const HTTPFetchRequest &fetch_request)
 430         {
 431                 Request req;
 432                 req.type = RT_FETCH;
 433                 req.fetch_request = fetch_request;
 434                 req.event = NULL;
 435                 m_requests.push_back(req);
 436         }
 437
 438         void requestClear(unsigned long caller, Event *event)
 439         {
 440                 Request req;
 441                 req.type = RT_CLEAR;
 442                 req.fetch_request.caller = caller;
 443                 req.event = event;
 444                 m_requests.push_back(req);
 445         }
 446
 447         void requestWakeUp()
 448         {
 449                 Request req;
 450                 req.type = RT_WAKEUP;
 451                 req.event = NULL;
 452                 m_requests.push_back(req);
 453         }
 454
 455 protected:
 456         // Handle a request from some other thread
 457         // E.g. new fetch; clear fetches for one caller; wake up
 458         void processRequest(const Request &req)
 459         {
 460                 if (req.type == RT_FETCH) {
 461                         // New fetch, queue until there are less
 462                         // than m_parallel_limit ongoing fetches
 463                         m_queued_fetches.push_back(req.fetch_request);
 464
 465                         // see processQueued() for what happens next
 466
 467                 }
 468                 else if (req.type == RT_CLEAR) {
 469                         unsigned long caller = req.fetch_request.caller;
 470
 471                         // Abort all ongoing fetches for the caller
 472                         for (std::vector<HTTPFetchOngoing*>::iterator
 473                                         it = m_all_ongoing.begin();
 474                                         it != m_all_ongoing.end();) {
 475                                 if ((*it)->getRequest().caller == caller) {
 476                                         delete (*it);
 477                                         it = m_all_ongoing.erase(it);
 478                                 } else {
 479                                         ++it;
 480                                 }
 481                         }
 482
 483                         // Also abort all queued fetches for the caller
 484                         for (std::list<HTTPFetchRequest>::iterator
 485                                         it = m_queued_fetches.begin();
 486                                         it != m_queued_fetches.end();) {
 487                                 if ((*it).caller == caller)
 488                                         it = m_queued_fetches.erase(it);
 489                                 else
 490                                         ++it;
 491                         }
 492                 }
 493                 else if (req.type == RT_WAKEUP) {
 494                         // Wakeup: Nothing to do, thread is awake at this point
 495                 }
 496
 497                 if (req.event != NULL)
 498                         req.event->signal();
 499         }
 500
 501         // Start new ongoing fetches if m_parallel_limit allows
 502         void processQueued(CurlHandlePool *pool)
 503         {
 504                 while (m_all_ongoing.size() < m_parallel_limit &&
 505                                 !m_queued_fetches.empty()) {
 506                         HTTPFetchRequest request = m_queued_fetches.front();
 507                         m_queued_fetches.pop_front();
 508
 509                         // Create ongoing fetch data and make a cURL handle
 510                         // Set cURL options based on HTTPFetchRequest
 511                         HTTPFetchOngoing *ongoing =
 512                                 new HTTPFetchOngoing(request, pool);
 513
 514                         // Initiate the connection (curl_multi_add_handle)
 515                         CURLcode res = ongoing->start(m_multi);
 516                         if (res == CURLE_OK) {
 517                                 m_all_ongoing.push_back(ongoing);
 518                         }
 519                         else {
 520                                 httpfetch_deliver_result(*ongoing->complete(res));
 521                                 delete ongoing;
 522                         }
 523                 }
 524         }
 525
 526         // Process CURLMsg (indicates completion of a fetch)
 527         void processCurlMessage(CURLMsg *msg)
 528         {
 529                 // Determine which ongoing fetch the message pertains to
 530                 size_t i = 0;
 531                 bool found = false;
 532                 for (i = 0; i < m_all_ongoing.size(); ++i) {
 533                         if (m_all_ongoing[i]->getEasyHandle() == msg->easy_handle) {
 534                                 found = true;
 535                                 break;
 536                         }
 537                 }
 538                 if (msg->msg == CURLMSG_DONE && found) {
 539                         // m_all_ongoing[i] succeeded or failed.
 540                         HTTPFetchOngoing *ongoing = m_all_ongoing[i];
 541                         httpfetch_deliver_result(*ongoing->complete(msg->data.result));
 542                         delete ongoing;
 543                         m_all_ongoing.erase(m_all_ongoing.begin() + i);
 544                 }
 545         }
 546
 547         // Wait for a request from another thread, or timeout elapses
 548         void waitForRequest(long timeout)
 549         {
 550                 if (m_queued_fetches.empty()) {
 551                         try {
 552                                 Request req = m_requests.pop_front(timeout);
 553                                 processRequest(req);
 554                         }
 555                         catch (ItemNotFoundException &e) {}
 556                 }
 557         }
 558
 559         // Wait until some IO happens, or timeout elapses
 560         void waitForIO(long timeout)
 561         {
 562                 fd_set read_fd_set;
 563                 fd_set write_fd_set;
 564                 fd_set exc_fd_set;
 565                 int max_fd;
 566                 long select_timeout = -1;
 567                 struct timeval select_tv;
 568                 CURLMcode mres;
 569
 570                 FD_ZERO(&read_fd_set);
 571                 FD_ZERO(&write_fd_set);
 572                 FD_ZERO(&exc_fd_set);
 573
 574                 mres = curl_multi_fdset(m_multi, &read_fd_set,
 575                                 &write_fd_set, &exc_fd_set, &max_fd);
 576                 if (mres != CURLM_OK) {
 577                         errorstream<<"curl_multi_fdset"
 578                                 <<" returned error code "<<mres
 579                                 <<std::endl;
 580                         select_timeout = 0;
 581                 }
 582
 583                 mres = curl_multi_timeout(m_multi, &select_timeout);
 584                 if (mres != CURLM_OK) {
 585                         errorstream<<"curl_multi_timeout"
 586                                 <<" returned error code "<<mres
 587                                 <<std::endl;
 588                         select_timeout = 0;
 589                 }
 590
 591                 // Limit timeout so new requests get through
 592                 if (select_timeout < 0 || select_timeout > timeout)
 593                         select_timeout = timeout;
 594
 595                 if (select_timeout > 0) {
 596                         // in Winsock it is forbidden to pass three empty
 597                         // fd_sets to select(), so in that case use sleep_ms
 598                         if (max_fd != -1) {
 599                                 select_tv.tv_sec = select_timeout / 1000;
 600                                 select_tv.tv_usec = (select_timeout % 1000) * 1000;
 601                                 int retval = select(max_fd + 1, &read_fd_set,
 602                                                 &write_fd_set, &exc_fd_set,
 603                                                 &select_tv);
 604                                 if (retval == -1) {
 605                                         #ifdef _WIN32
 606                                         errorstream<<"select returned error code "
 607                                                 <<WSAGetLastError()<<std::endl;
 608                                         #else
 609                                         errorstream<<"select returned error code "
 610                                                 <<errno<<std::endl;
 611                                         #endif
 612                                 }
 613                         }
 614                         else {
 615                                 sleep_ms(select_timeout);
 616                         }
 617                 }
 618         }
 619
 620         void * Thread()
 621         {
 622                 ThreadStarted();
 623                 log_register_thread("CurlFetchThread");
 624                 DSTACK(__FUNCTION_NAME);
 625
 626                 porting::setThreadName("CurlFetchThread");
 627
 628                 CurlHandlePool pool;
 629
 630                 m_multi = curl_multi_init();
 631                 if (m_multi == NULL) {
 632                         errorstream<<"curl_multi_init returned NULL\n";
 633                         return NULL;
 634                 }
 635
 636                 FATAL_ERROR_IF(!m_all_ongoing.empty(), "Expected empty");
 637
 638                 while (!StopRequested()) {
 639                         BEGIN_DEBUG_EXCEPTION_HANDLER
 640
 641                         /*
 642                                 Handle new async requests
 643                         */
 644
 645                         while (!m_requests.empty()) {
 646                                 Request req = m_requests.pop_frontNoEx();
 647                                 processRequest(req);
 648                         }
 649                         processQueued(&pool);
 650
 651                         /*
 652                                 Handle ongoing async requests
 653                         */
 654
 655                         int still_ongoing = 0;
 656                         while (curl_multi_perform(m_multi, &still_ongoing) ==
 657                                         CURLM_CALL_MULTI_PERFORM)
 658                                 /* noop */;
 659
 660                         /*
 661                                 Handle completed async requests
 662                         */
 663                         if (still_ongoing < (int) m_all_ongoing.size()) {
 664                                 CURLMsg *msg;
 665                                 int msgs_in_queue;
 666                                 msg = curl_multi_info_read(m_multi, &msgs_in_queue);
 667                                 while (msg != NULL) {
 668                                         processCurlMessage(msg);
 669                                         msg = curl_multi_info_read(m_multi, &msgs_in_queue);
 670                                 }
 671                         }
 672
 673                         /*
 674                                 If there are ongoing requests, wait for data
 675                                 (with a timeout of 100ms so that new requests
 676                                 can be processed).
 677
 678                                 If no ongoing requests, wait for a new request.
 679                                 (Possibly an empty request that signals
 680                                 that the thread should be stopped.)
 681                         */
 682                         if (m_all_ongoing.empty())
 683                                 waitForRequest(100000000);
 684                         else
 685                                 waitForIO(100);
 686
 687                         END_DEBUG_EXCEPTION_HANDLER(errorstream)
 688                 }
 689
 690                 // Call curl_multi_remove_handle and cleanup easy handles
 691                 for (size_t i = 0; i < m_all_ongoing.size(); ++i) {
 692                         delete m_all_ongoing[i];
 693                 }
 694                 m_all_ongoing.clear();
 695
 696                 m_queued_fetches.clear();
 697
 698                 CURLMcode mres = curl_multi_cleanup(m_multi);
 699                 if (mres != CURLM_OK) {
 700                         errorstream<<"curl_multi_cleanup"
 701                                 <<" returned error code "<<mres
 702                                 <<std::endl;
 703                 }
 704
 705                 return NULL;
 706         }
 707 };
 708
 709 CurlFetchThread *g_httpfetch_thread = NULL;
 710
 711 void httpfetch_init(int parallel_limit)
 712 {
 713         verbosestream<<"httpfetch_init: parallel_limit="<<parallel_limit
 714                         <<std::endl;
 715
 716         CURLcode res = curl_global_init(CURL_GLOBAL_DEFAULT);
 717         FATAL_ERROR_IF(res != CURLE_OK, "CURL init failed");
 718
 719         g_httpfetch_thread = new CurlFetchThread(parallel_limit);
 720 }
 721
 722 void httpfetch_cleanup()
 723 {
 724         verbosestream<<"httpfetch_cleanup: cleaning up"<<std::endl;
 725
 726         g_httpfetch_thread->Stop();
 727         g_httpfetch_thread->requestWakeUp();
 728         g_httpfetch_thread->Wait();
 729         delete g_httpfetch_thread;
 730
 731         curl_global_cleanup();
 732 }
 733
 734 void httpfetch_async(const HTTPFetchRequest &fetch_request)
 735 {
 736         g_httpfetch_thread->requestFetch(fetch_request);
 737         if (!g_httpfetch_thread->IsRunning())
 738                 g_httpfetch_thread->Start();
 739 }
 740
 741 static void httpfetch_request_clear(unsigned long caller)
 742 {
 743         if (g_httpfetch_thread->IsRunning()) {
 744                 Event event;
 745                 g_httpfetch_thread->requestClear(caller, &event);
 746                 event.wait();
 747         }
 748         else {
 749                 g_httpfetch_thread->requestClear(caller, NULL);
 750         }
 751 }
 752
 753 void httpfetch_sync(const HTTPFetchRequest &fetch_request,
 754                 HTTPFetchResult &fetch_result)
 755 {
 756         // Create ongoing fetch data and make a cURL handle
 757         // Set cURL options based on HTTPFetchRequest
 758         CurlHandlePool pool;
 759         HTTPFetchOngoing ongoing(fetch_request, &pool);
 760         // Do the fetch (curl_easy_perform)
 761         CURLcode res = ongoing.start(NULL);
 762         // Update fetch result
 763         fetch_result = *ongoing.complete(res);
 764 }
 765
 766 #else  // USE_CURL
 767
 768 /*
 769         USE_CURL is off:
 770
 771         Dummy httpfetch implementation that always returns an error.
 772 */
 773
 774 void httpfetch_init(int parallel_limit)
 775 {
 776 }
 777
 778 void httpfetch_cleanup()
 779 {
 780 }
 781
 782 void httpfetch_async(const HTTPFetchRequest &fetch_request)
 783 {
 784         errorstream << "httpfetch_async: unable to fetch " << fetch_request.url
 785                         << " because USE_CURL=0" << std::endl;
 786
 787         HTTPFetchResult fetch_result(fetch_request); // sets succeeded = false etc.
 788         httpfetch_deliver_result(fetch_result);
 789 }
 790
 791 static void httpfetch_request_clear(unsigned long caller)
 792 {
 793 }
 794
 795 void httpfetch_sync(const HTTPFetchRequest &fetch_request,
 796                 HTTPFetchResult &fetch_result)
 797 {
 798         errorstream << "httpfetch_sync: unable to fetch " << fetch_request.url
 799                         << " because USE_CURL=0" << std::endl;
 800
 801         fetch_result = HTTPFetchResult(fetch_request); // sets succeeded = false etc.
 802 }
 803
 804 #endif  // USE_CURL